Recovery of Lithium Carbonate From

Europäisches Patentamt *EP001286917B1* (19) European Patent Office

Office européen des brevets (11) EP 1 286 917 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Date of publication and mention (51) Int Cl.7: C01D 15/04 of the grant of the patent: 09.03.2005 Bulletin 2005/10 (86) International application number: PCT/SE2001/000913 (21) Application number: 01926300.3 (87) International publication number: (22) Date of filing: 27.04.2001 WO 2001/083372 (08.11.2001 Gazette 2001/45)

(54) RECOVERY OF LITHIUM CARBONATE FROM CONTAMINATED LITHIUM BROMIDE RÜCKGEWINNUNG VON LITHIUMKARBONAT AUS KONTAMINIERTEM LITHIUMBROMID RECUPERATION DE CARBONATE DE LITHIUM A PARTIR DE BROMURE DE LITHIUM CONTAMINE

(84) Designated Contracting States: (74) Representative: Gulliksson, Jonas AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU Ström & Gulliksson AB MC NL PT SE TR Studentgatan 1 P.O. Box 4188 (30) Priority: 03.05.2000 SE 0001607 203 13 Malmö (SE)

(43) Date of publication of application: (56) References cited: 05.03.2003 Bulletin 2003/10 • DATABASE WPI Week 197813, Derwent Publications Ltd., London, GB; AN 1978-24408A, (73) Proprietor: Olsson, Bozena Nenna XP002957072 & JP 53 017 590 A (HITACHI LTD) 246 21 Löddeköpinge (SE) 17 February 1978 • DATABASE WPI Week 199824, Derwent (72) Inventor: Olsson, Bozena Nenna Publications Ltd., London, GB; AN 1998-264504, 246 21 Löddeköpinge (SE) XP002957073 & JP 9 236 358 A (MITSUBISHI RAYON CO LTD) 09 September 1997 • GUNNAR HAGG: ’Allman och oorganisk kemi’ ATTONDE UPPLAGAN, ALMQVIST & WIKSELL page 565, 337

Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). EP 1 286 917 B1

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Description ground as above. The storage of these large quantities of discarded lithium bromide also occupies large areas FIELD OF INVENTION within the industry, areas, which could be used for other more economic purposes. [0001] The invention relates to a method and plant for 5 [0005] There is an increased demand from both na- the recovery of lithium carbonate from contaminated ture and different groups of people that we should try to lithium bromide. The lithium bromide, being contaminat- reuse as much as possible to reduce the still increasing ed with metals and/or organic compounds and the car- mountain of different kinds of waste and also try to min- bonate preferably being sodium carbonate. Preferably, imise the reduction of our limiting nature resources. To- the lithium carbonate is recovered using sodium carbon- 10 day there is no method available for the recovery of dis- ate carded contaminated lithium bromide solutions. [0006] A method for the recovery of contaminated dis- BACKGROUND OF INVENTION carded lithium bromide would reduce the amount of discarded contaminated lithium bromide and furthermore [0002] Lithium bromide (LiBr) is used in large quanti- 15 reduce the pressure of toxic bromides on the environ- ties in several applications such as heating pumps and ment. cooling systems including refrigerators. One example is absorption heating pumps used to provide energy to BRIEF DISCLOSURE OF THE INVENTION households. In Sweden there a total waste of approxi- mately 73 million tons of LiBr and 62 million tons are 20 [0007] The object of the present invention is to provide waste from the industry. The reasons why lithium bro- an economic method and a plant for the recovery of lith- mide solutions are discarded depends on several fac- ium carbonate from contaminated lithium bromide, such tors such as the concentration of antifoam agents and/ as discarded lithium bromide. By the availability of such or anticorrosive agents are to high or to low in the lithium a method the recovered lithium carbonate may econom- bromide solution when the solution is delivered from the 25 ically be reused in several industries, such as the lithium manufacture. Furthermore, often contaminants arise battery industry, the concrete industry, by ceramics and during the use of the lithium bromide solution in a plant, in the production of clinkers and tiles. a plant in which the lithium bromide, circulate in a closed [0008] Preferably, the recovery of lithium carbonate systems. The total result is that the lithium bromide so- utilises sodium carbonate for the recovery of lithium car- lution contain large amounts of contaminants, such as 30 bonate from lithium bromide. Hereby both lithium car- metals, organic compounds such as toxic compounds, bonate and sodium bromide are recovered as final prod- or other organic or unorganic substances, such as chlo- ucts. The recovered sodium bromide may be reused in rine, iron, chromium, sulphur, copper, antifoam, ten- the pulp industry or other industries where there is a sides, anticorrosive agents etc. need of an antibacterial- and/or antimould-agent. [0003] Today, it is not possible to deposit discarded 35 [0009] In a first embodiment, the invention relates to lithium bromide solutions in Sweden due to the pres- a method for recovery of lithium carbonate recovery ence of environmental hazardous substances in the dis- from a metal contaminated lithium bromide comprising carded lithium bromide such as the environmental haz- the steps of; providing a solution of the metal contami- ard bromide. The large amounts of discarded lithium nated lithium bromide; heating the metal contaminated carbonate are therefor deposited in large containers 40 lithium bromide to a temperature of from about 25 to within the industry. During the storage of the discarded about 45° C; maintaining the temperature throughout lithium bromides, in solution or in a dried form, leach the method, adding sodium carbonate in solid form to water may arise. Leach water containing the above the heated metal contaminated lithium bromide solution mentioned environmental hazardous substances. The and precipitating solid lithium carbonate. leach water may find the way out into the ground water 45 [0010] In a second aspect, the invention relates to a and the ground resulting in that the environmental haz- method of lithium carbonate recovery from an organic ardous substances end up in the ground water and in compound contaminated lithium bromide comprising the ground and is exposed to microorganisms and fish- the steps of; creating a solution of the organic compound es. These environmental hazardous substances are of- contaminated lithium bromide; adding saturated sodium ten toxic for both microorganisms and fishes, which are 50 carbonate preheated to a temperature of 25 -45° Cto one of the reasons why they are not allowed to be de- the organic compound contaminated lithium bromide posited directly in our environment. One example of a solution and precipitation of solid lithium carbonate. toxic substance is bromide, which is present in large [0011] Accordingly, the invention relates to a plant in quantities in lithium bromide solutions. which the methods are used and the use of the recov- [0004] Sometimes the storage of discarded lithium 55 ered lithium carbonate. bromide solutions result in that the container used for [0012] The invention provides completely new eco- the storage break and the discarded lithium bromide so- nomic method for the recovery of lithium carbonate from lution leach out and reach the ground water and the discarded contaminated lithium bromide, which reduces

2 3 EP 1 286 917 B1 4 the problems of poisoning the ground water and the erably be heated to a temperature above 35° C and a ground with bromides which are toxic for microorgan- metal contaminated lithium bromide solution having a isms and fishes, reduced the waste with our nature re- concentration of ≥ 25% may preferably be heated to a sources and furthermore provide the market with eco- temperature above 25° C. A metal contaminated lithium nomically interesting lithium carbonate. 5 bromide solution having a concentration of from about 10% to about 25% may be heated to a temperature of DETAILED DESCRIPTION OF THE INVENTION at least 25° C. [0021] However, the temperature is also dependent [0013] The invention relates to a method and plant for on the concentration of the contaminating metals such the recovery of lithium carbonate from contaminated 10 as a contamination of about 49 µg/l of one or more met- lithium bromide. The lithium bromide may be discarded als, the metal contaminated lithium bromide solution lithium bromide which may be discarded from heating may be heated to a temperature from about 30 °Cto pumps, ventilation systems, absorption heating pumps, about 35° C and a contamination of 50 µg/l of one or refrigerators or any other sources from which the lithium more metals, the metal contaminated lithium bromide bromide is supposed to be discarded. 15 solution may be heated to a temperature from about 35 [0014] The lithium bromide may be contaminated by ° C to about 45° C. metals and/or organic compounds. Metals such as [0022] After the metal contaminated lithium bromide Cu2+,Cr3+,Cr6+,Fe2+ and/or organic compounds such solution has been heated, the solution is maintained at as tensides, anticorrosive agents and antifoaming that temperature throughout the method to secure the agents. Tensides, anticorrosive agents and antifoaming 20 contaminating metals remains in solution. agents well-known to a person skilled in the art. [0023] Carbonate is the added in a solid form to the [0015] Depending on if lithium bromide is contaminat- heated metal contaminated lithium bromide solution, ed with metals or organic substances, slightly different preferably the carbonate is sodium carbonate. The car- methods are necessary to use to enable a successful bonate may be added in an amount of from about 0.1 to recovery of lithium carbonate. 25 about 31 g/l of metal contaminated lithiumbromide solution. Preferably the added carbonate is a carbonate Recovery of lithium carbonate from lithium bromide solution such as sodium carbonate and added in a con- contaminated with metals. centration of 50 % (weight/volume). The carbonate is preferably added under stirring of the lithium bromide [0016] We have surprisingly found that by the use of 30 solution. Carbonate is added continuously and lithium a preheated lithium bromide solution during our recov- carbonate start to precipitate in the form of solid lithium ery method it is possible to obtain a lithium carbonate carbonate. However, the metals remain in the solution being substantially free from the contaminating metals. due to the increased temperature of the metal contam- [0017] The metal contaminated lithium bromides are inated lithium bromide solution and thereby the metals discarded lithium bromides such as lithium bromides 35 are separated from lithium and enables the possibility that have been used in heating pumps and cooling to obtain lithium carbonate which is substantially free plants including refrigerators. These metal contaminat- from metals. ed lithium bromides may be contaminated with one or [0024] When sodium carbonate is used as carbonate more metals such as Cu2+,Cr3+,Cr6+,Fe2+, preferably source, a metal containing sodium bromide solution is Cr3+ and Cr6+. The metals may bind more or less strong- 40 obtained together with the solid lithium carbonate. The ly to lithium and thereby render it more difficult to recover metal containing sodium bromide solution may be fur- lithium in the form of lithium carbonate. ther purified using methods well-known for a person [0018] The method according to the present invention skilled in the art, such as ion exchangers selective for makes use of several steps through out the method, certain metal ions to obtain purer forms of sodium bro- which makes the recovery of lithium in the form of lithium 45 mide. carbonate possible. Firstly the metal contaminated lith- [0025] The precipitated lithium carbonate is at least ium bromides are provided in the form of a solution. The 90 % pure lithium carbonate, such as from about 90 % metal contaminated lithium bromide solution is heated to 100 % pure lithium carbonate, or from about 95 % to to a temperature of from about 25 to about 45° C, such 100 % pure lithium carbonate or from about 98 % to 100 as from about 30° C to about 45° C or from about 35° 50 % pure lithium carbonate or 99.1 %, 99.2 %, 99.3 %, C to about 40° C to enable a successful separation of 99.4 %, 99.5 %, 99.6 %, 99.7 %, 99. 8 % or 99.9 % pure the contaminating metals from lithium. lithium carbonate. [0019] The temperature to be chosen depends [0026] The precipitated lithium carbonate may further among others, the concentration on the metal contami- be dried at a temperature of < 600 °C, such as from nated lithium bromide solution and/or the concentration 55 about 100 °C to about 600 °C, preferably > 100 °C. of the contaminating metals. [0027] The metals including the toxic bromide remain [0020] For example a metal contaminated lithium bro- in the solution and may be recovered therefrom by other mide solution having a concentration of ≤ 10 % may pref- methods.

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[0028] The recovered lithium carbonate may be used to 100 % pure lithium carbonate, or from about 95 % to in several industries such as the production of lithium 100 % pure lithium carbonate or from about 98 % to 100 batteries, the concrete industry, by ceramics and in the % pure lithium carbonate or 99.1 %, 99.2 %, 99.3 %, production of clinkers and tiles. 99.4 %, 99.5 %, 99.6 %, 99.7 %, 99. 8 % or 99.9 % pure [0029] When sodium carbonate is used for the recov- 5 lithium carbonate. ery of lithium carbonate, the sodium bromide solution [0036] The precipitated lithium carbonate may further may be reused in the pulp industry or other industries be dried at a temperature of < 600 ° C, such as from where there is a need of an antibacterial- and/or anti- about 100 ° C to about 600° C, preferably > 100 °C. mould-agent. [0037] The recovered lithium carbonate may be used [0030] The method for recovery of lithium carbonate 10 in several industries such as the production of lithium from a metal contaminated lithium bromide may be used batteries, the concrete industry, by ceramics and in the alone or in combination with the method mentioned be- production of clinkers and tiles. low in the case a discarded lithium bromide being con- [0038] Furthermore the invention relates to a plant us- taminated with both one or more metals and one or more ing one or both of the above mentioned methods. The organic compounds. When both of the methods are 15 plant may preferably be a closed system needed, the order in which the two methods are com- [0039] Additionally the invention relates to use of lith- bined are of no importance and may vary. ium carbonate which has been recovered, from discarded contaminated lithium bromide by the methods ac- Recovery of lithium carbonate from lithium bromide cording to the invention. The lithium bromide, being con- contaminated with organic compounds. 20 taminated with one or more metals and/or organic compounds. The invention also relates to use of sodium bro- [0031] We have surprisingly found that by the use of mide when sodium carbonate is used for the recovery a preheated saturated carbonate, such as sodium car- of lithium carbonate. bonate during recovery of lithium carbonate from an organic compound contaminated lithium bromide solution 25 EXAMPLES it is possible to obtain a lithium carbonate being substantially free from the contaminating organic com- EXAMPLE 1 pounds. [0032] The organic compound contaminated lithium [0040] 100 litre 10 % (weight/volume) of LiBr-solution bromides may be discarded lithium bromides such as 30 contaminated with 49 µg/l of Cr2+ was preheated to a lithium bromides that have been used in heating pumps temperature of 40 ° C. 6.1 kg of solid sodium carbonate and cooling plants including refrigerators to replace fre- was added under stirring of the LiBr-solution. The tem- on. These organic contaminated lithium bromides may perature was kept constant. 4.25 kg of lithium carbonate be contaminated with one or more organic compounds were precipitated in the form of a lithium carbonate cake such as tensides, anticorrosive agents and antifoaming 35 and 100 litre of sodium bromide in solution. The sodium agents. bromide solution also contained 49 µg/l of Cr2+ and was [0033] The method according to the present invention further treated using a selective ion exchangers. The makes use of several steps through out the method, lithium carbonate cake was found to be 99.6 % pure lith- which makes the recovery of lithium in the form of lithium ium carbonate. carbonate possible. Firstly the organic contaminated 40 lithium bromides are provided in the form of a solution EXAMPLE 2 obtained either directly from the contaminated lithium bromide or after the contaminated lithium bromide has [0041] 100 litre 50 % (weight/volume) of LiBr-solution been separated from contaminating metals using the contaminated with 50 µg/l of antifoam agent held at a method described above. 45 temperature of 25° C. Saturated sodium carbonate was [0034] Then carbonate is added in a saturated pre- added to the LiBr-solution under stirring of the LiBr-so- heated from, preheated to a temperature of from about lution. The mixture was heated to a temperature of 30° 25 -45° C, such as from about 35° C to about 45° C. C and 421.25 kg of lithium carbonate were precipitated Preferably the carbonate is sodium carbonate such as in the form of a lithium carbonate cake and 100 litre of in example 2. The carbonate is added under stirring of 50 sodium bromide in solution containing the antifoam the organic compound contaminated lithium bromide agent. The lithium carbonate cake was found to be 99.6 solution. Carbonate is added continuously and lithium % pure lithium carbonate. carbonate start to precipitate in the form of solid lithium [0042] Preparation of saturated sodium carbonate: carbonate. However, the organic compounds remain in the solution and thereby the organic compounds are 55 30.5 kg of solid sodium carbonate was mixed with separated from lithium. 60.4 litre of water prior addition to the lithium bro- [0035] The precipitated lithium carbonate is at least mide solution. 90 % pure lithium carbonate, such as from about 90 %

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Claims 10. The method according to any of the claims 7-9, wherein the carbonate used in step b) is sodium car- 1. A method for recovery of lithium carbonate from a bonate and lithium carbonate is precipitated and so- metal contaminated lithium bromide comprising the dium bromide obtained as a solution in step c). steps of 5 11. The method according to any of the preceding a) providing a solution of the metal contaminat- claims, wherein the precipitated solid lithium car- ed lithium bromide, bonate is at least 90 % pure lithium carbonate. b) heating the metal contaminated lithium bromide to a temperature of from about 25 to about 10 12. The method according to any of the preceding 45° C, claims, wherein the precipitated solid lithium car- c) maintaining the temperature throughout the bonate is from about 90 % to 100 % pure lithium method, carbonate. d) adding carbonate in solid form to the heated metal contaminated lithium bromide solution 15 13. The method according to claim 9, wherein the pre- and cipitated solid lithium carbonate is from about 95 % e) precipitating solid lithium carbonate. to 100 % pure lithium carbonate.

2. Method according to claim 1, wherein the lithium 14. The method according to claims 9-10, wherein the bromide is contaminated with a metal selected from 20 precipitated solid lithium carbonate is from about 98 the group consisting of Cu2+,Cr3+,Cr6+,Fe2+ and % to 100 % pure lithium carbonate. Fe3+. 15. A method for the recovery of lithium carbonate from 3. Method according to claim 2, wherein the metal is a contaminated lithium bromide, wherein the meth- selected from the group consisting of Cr3+ and Cr6+. 25 od according to any of the claims 1-6 is combined with any of the claims 7-14. 4. Method according to any of the preceding claims, wherein the temperature is from about 30° Cto about 45° C. Patentansprüche 30 5. The method according to claim 4, wherein the tem- 1. Verfahren zur Rückgewinnung von Lithiumcarbonat perature is from about 35° C to about 40° C. aus metallverunreinigtem Lithiumbromid, bei dem man: 6. The method according to any of the preceding claims, wherein the carbonate used in step d) is so- 35 a) eine Lösung des metallverunreinigten Lithi- dium carbonate and lithium carbonate is precipitat- umbromids bereitstellt, ed and sodium bromide obtained as a solution in b) das metallverunreinigte Lithiumbromid auf step e). eine Temperatur von etwa 25 bis etwa 45°C er- wärmt, 7. A method of lithium carbonate recovery from an or- 40 c) die Temperatur über das gesamte Verfahren ganic compound contaminated lithium bromide hinweg aufrechterhält, comprising the steps of d) die erwärmte Lösung von metallverunreinigtem Lithiumbromid mit Carbonat in fester Form a) creating a solution of the organic compound versetzt und contaminated lithium bromide, 45 e) festes Lithiumcarbonat ausfällt. b) adding saturated carbonate preheated to a temperature of 25 -45° C to the organic com- 2. Verfahren nach Anspruch 1, bei dem das Lithium- pound contaminated lithium bromide solution bromid mit einem Metall aus der Gruppe bestehend and aus Cu2+,Cr3+,Crb+,Fe2+ und Fe3+ verunreinigt ist. c) precipitation of solid lithium carbonate 50 3. Verfahren nach Anspruch 2, bei dem das Metall aus 8. Method according to claim 7, wherein the lithium der Gruppe bestehend aus Cr3+ und Cr6+ stammt. bromide is contaminated with an organic compound selected from the group consisting of tensides, an- 4. Verfahren nach einem der vorhergehenden Ansprü- ticorrosive agents and antifoaming agents. 55 che, bei dem die Temperatur etwa 30°C bis etwa 45°C beträgt. 9. Method according to any of the claims 7-8, wherein the temperature is from about 35° C to about 45° C. 5. Verfahren nach Anspruch 4, bei dem die Tempera-

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tur etwa 35°C bis etwa 40°C beträgt. Revendications

6. Verfahren nach einem der vorhergehenden Ansprü- 1. Procédé de récupération de carbonate de lithium à che, bei dem man als Carbonat in Schritt d) Natri- partir de bromure de lithium contaminé par un métal umcarbonat verwendet, Lithiumcarbonat ausfällt 5 comprenant les étapes consistant à und als Lösung in Schritt e) Natriumbromid erhält. a) fournir une solution du bromure de lithium 7. Verfahren zur Rückgewinnung von Lithiumcarbonat contaminé par un métal, aus mit einer organischen Verbindung verunreinig- b) chauffer le bromure de lithium contaminé par tem Lithiumbromid, bei dem man 10 un métal à une température comprise dans la plage allant d'environ 25 à environ 45 °C, a) eine Lösung des mit einer organischen Ver- c) maintenir la température tout au long du pro- bindung verunreinigten Lithiumbromids her- cédé, stellt, d) ajouter le carbonate sous une forme solide b) die Lösung von mit einer organischen Ver- 15 à la solution chauffée de bromure de lithium bindung verunreinigtem Lithiumbromid mit auf contaminé par un métal, et eine Temperatur von 25-45°C vorgewärmtem e) précipiter le carbonate de lithium solide. gesättigtem Carbonat versetzt und c) festes Lithiumcarbonat ausfällt. 2. Procédé selon la revendication 1, dans lequel le 20 bromure de lithium est contaminé par un métal choi- 8. Verfahren nach Anspruch 7, bei dem das Lithium- si dans le groupe comprenant Cu2+,Cr3+,Cr6+, bromid mit einer organischen Verbindung aus der Fe2+ et Fe3+. Gruppe bestehend aus Tensiden, Korrosions- schutzmitteln und Antischaummitteln verunreinigt 3. Procédé selon la revendication 2, dans lequel le ist. 25 métal est choisi dans le groupe comprenant Cr3+ et Cr6+. 9. Verfahren nach einem der Ansprüche 7-8, bei dem die Temperatur etwa 35°C bis etwa 45°C beträgt. 4. Procédé selon l'une quelconque des revendications précédentes, dans lequel la température est com- 10. Verfahren nach einem der Ansprüche 7-9, bei dem 30 prise dans la plage allant d'environ 30 °C à environ man als Carbonat in Schritt b) Natriumcarbonat ver- 45 °C. wendet, Lithiumcarbonat ausfällt und als Lösung in Schritt c) Natriumbromid erhält. 5. Procédé selon la revendication 4, dans lequel la température est comprise dans la plage allant d'en- 11. Verfahren nach einem der vorhergehenden Ansprü- 35 viron 35 °C à environ 40 °C. che, bei dem das ausgefällte feste Lithiumcarbonat eine Reinheit von mindestens 90% aufweist. 6. Procédé selon l'une quelconque des revendications précédentes, dans lequel le carbonate utilisé dans 12. Verfahren nach einem der vorhergehenden Ansprü- l'étape d) est le carbonate de sodium et le carbonate che, bei dem das ausgefällte feste Lithiumcarbonat 40 de lithium est précipité et le bromure de sodium ob- eine Reinheit von etwa 90 bis 100% aufweist. tenu sous la forme d'une solution dans l'étape e).

13. Verfahren nach Anspruch 9, bei dem das ausgefäll- 7. Procédé de récupération de carbonate de lithium à te feste Lithiumcarbonat eine Reinheit von etwa 95 partir de bromure de lithium contaminé par un com- bis 100% aufweist. 45 posé organique comprenant les étapes consistant à

14. Verfahren nach einem der Ansprüche 9-10, bei dem a) créer une solution du bromure de lithium con- das ausgefällte feste Lithiumcarbonat eine Reinheit taminé par un composé organique, von etwa 98 bis 100% aufweist. b) ajouter le carbonate saturé préchauffé à une 50 température comprise dans la plage allant de 15. Verfahren zur Rückgewinnung von Lithiumcarbonat 25 à 45 °C à la solution de bromure de lithium aus verunreinigtem Lithiumbromid, bei dem man contaminé par un composé organique, et das Verfahren nach einem der Ansprüche 1-6 mit c) précipiter le carbonate de lithium solide. einem der Ansprüche 7-14 kombiniert. 55 8. Procédé selon la revendication 7, dans lequel le bromure de lithium est contaminé par un composé organique choisi dans le groupe comprenant des tensioactifs, des agents anticorrosifs et des agents

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antimousses.

9. Procédé selon l'une quelconque des revendications 7 et 8, dans lequel la température est comprise dans la plage allant d'environ 35 °C à environ 45 °C. 5

10. Procédé selon l'une quelconque des revendications 7 à 9, dans lequel le carbonate utilisé dans l'étape b) est le carbonate de sodium et le carbonate de lithium est précipité et le bromure de sodium obtenu 10 sous la forme d'une solution dans l'étape c).

11. Procédé selon l'une quelconque des revendications précédentes, dans lequel le carbonate de lithium solide précipité est du carbonate de lithium pur à au 15 moins 90%.

12. Procédé selon l'une quelconque des revendications précédentes, dans lequel le carbonate de lithium solide précipité est du carbonate de lithium 90 % à 20 100 % pur.

13. Procédé selon la revendication 9, dans lequel le carbonate de lithium solide précipité est du carbonate de lithium 95 % à 100 % pur. 25

14. Procédé selon l'une quelconque des revendications 9 et 10, dans lequel le carbonate de lithium solide précipité est du carbonate de lithium 98 % à 100 % pur. 30

15. Procédé de récupération de carbonate de lithium à partir de bromure de lithium contaminé, dans lequel le procédé selon l'une quelconque des revendications 1 à 6 est combiné au procédé selon l'une quel- 35 conque des revendications 7 à 14.